0034-7450 0034-7450 S0034-74502020000200121 10.1016/j.rcp.2018.05.003 Venezuela 00 06 2020 00 06 2020 49 2 121 126

1 1909 7th 2 2015 57 409-26 3 1990 4 2017 2 265-96 5 2016 1-34 6 1991 7 1999 8 2010 9 1909 6 10 2009 11 1909 6 12 1999 13 2000